feat: make to address optional for transaction data (#2852)

## What ❔

This PR is the first part of [this
one](#2631).

We decided to separate it into smaller PRs to make it easier to read and
review.

This PR contains only the changes to the `TransactionData` structs for
the different VM versions, modifying them for an optional field.

The other parts are currently available in our repo fork, as they are
based on this branch. The other PRs are:
- [feat: evm simulator as base system
contract](lambdaclass#256):
integrates the EVM interpreter contract as a base system contract and
includes all necessary updates for zksync-era to run with it.
- [feat: make evm simulator optional for the
server](lambdaclass#257): makes the
evm simulator optional to run using a config file.

## Why ❔

<!-- Why are these changes done? What goal do they contribute to? What
are the principles behind them? -->
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iterators are in context about the evolution of repos. -->

## Checklist

<!-- Check your PR fulfills the following items. -->
<!-- For draft PRs check the boxes as you complete them. -->

- [ ] PR title corresponds to the body of PR (we generate changelog
entries from PRs).
- [ ] Tests for the changes have been added / updated.
- [ ] Documentation comments have been added / updated.
- [ ] Code has been formatted via `zk fmt` and `zk lint`.

core/bin/system-constants-generator/src/utils.rs

@@ -89,7 +89,7 @@ pub(super) fn get_l2_tx(
     pubdata_price: u32,
 ) -> L2Tx {
     L2Tx::new_signed(
-        contract_address,
+        Some(contract_address),
         vec![],
         Nonce(0),
         Fee {
@@ -134,7 +134,7 @@ pub(super) fn get_l1_tx(
 ) -> L1Tx {
     L1Tx {
         execute: Execute {
-            contract_address,
+            contract_address: Some(contract_address),
             calldata: custom_calldata.unwrap_or_default(),
             value: U256::from(0),
             factory_deps,

core/lib/dal/src/consensus/mod.rs

@@ -401,9 +401,10 @@ impl ProtoRepr for proto::Transaction {
                 }
             },
             execute: Execute {
-                contract_address: required(&execute.contract_address)
-                    .and_then(|x| parse_h160(x))
-                    .context("execute.contract_address")?,
+                contract_address: execute
+                    .contract_address
+                    .as_ref()
+                    .and_then(|x| parse_h160(x).ok()),
                 calldata: required(&execute.calldata).context("calldata")?.clone(),
                 value: required(&execute.value)
                     .and_then(|x| parse_h256(x))
@@ -487,7 +488,7 @@ impl ProtoRepr for proto::Transaction {
             }
         };
         let execute = proto::Execute {
-            contract_address: Some(this.execute.contract_address.as_bytes().into()),
+            contract_address: this.execute.contract_address.map(|x| x.as_bytes().into()),
             calldata: Some(this.execute.calldata.clone()),
             value: Some(u256_to_h256(this.execute.value).as_bytes().into()),
             factory_deps: this.execute.factory_deps.clone(),

core/lib/dal/src/consensus/proto/mod.proto

@@ -102,7 +102,7 @@ message ProtocolUpgradeTxCommonData {
 }
 
 message Execute {
-  optional bytes contract_address = 1; // required; H160
+  optional bytes contract_address = 1; // optional; H160
   optional bytes calldata = 2; // required
   optional bytes value = 3; // required; U256
   repeated bytes factory_deps = 4;

core/lib/dal/src/consensus/tests.rs

@@ -17,7 +17,7 @@ use crate::tests::mock_protocol_upgrade_transaction;
 
 fn execute(rng: &mut impl Rng) -> Execute {
     Execute {
-        contract_address: rng.gen(),
+        contract_address: Some(rng.gen()),
         value: rng.gen::<u128>().into(),
         calldata: (0..10 * 32).map(|_| rng.gen()).collect(),
         // TODO: find a way to generate valid random bytecode.

core/lib/dal/src/models/tests.rs

@@ -13,7 +13,7 @@ use crate::{models::storage_transaction::StorageTransaction, BigDecimal};
 
 fn default_execute() -> Execute {
     Execute {
-        contract_address: H160::random(),
+        contract_address: Some(H160::random()),
         value: U256::from(10i32),
         calldata: hex::decode(
             "a9059cbb00000000000000000000000058d595f318167d5af45d9e44ade4348dd4e\

core/lib/dal/src/tests/mod.rs

@@ -74,7 +74,7 @@ pub(crate) fn mock_l2_transaction() -> L2Tx {
         gas_per_pubdata_limit: U256::from(DEFAULT_GAS_PER_PUBDATA),
     };
     let mut l2_tx = L2Tx::new_signed(
-        Address::random(),
+        Some(Address::random()),
         vec![],
         zksync_types::Nonce(0),
         fee,
@@ -110,7 +110,7 @@ pub(crate) fn mock_l1_execute() -> L1Tx {
     };
 
     let execute = Execute {
-        contract_address: H160::random(),
+        contract_address: Some(H160::random()),
         value: Default::default(),
         calldata: vec![],
         factory_deps: vec![],
@@ -138,7 +138,7 @@ pub(crate) fn mock_protocol_upgrade_transaction() -> ProtocolUpgradeTx {
     };
 
     let execute = Execute {
-        contract_address: H160::random(),
+        contract_address: Some(H160::random()),
         value: Default::default(),
         calldata: vec![],
         factory_deps: vec![],

core/lib/dal/src/transactions_dal.rs

@@ -58,7 +58,8 @@ impl TransactionsDal<'_, '_> {
         tx: &L1Tx,
         l1_block_number: L1BlockNumber,
     ) -> DalResult<()> {
-        let contract_address = tx.execute.contract_address.as_bytes();
+        let contract_address = tx.execute.contract_address;
+        let contract_address_as_bytes = contract_address.map(|addr| addr.as_bytes().to_vec());
         let tx_hash = tx.hash();
         let tx_hash_bytes = tx_hash.as_bytes();
         let json_data = serde_json::to_value(&tx.execute)
@@ -143,7 +144,7 @@ impl TransactionsDal<'_, '_> {
             serial_id,
             full_fee,
             layer_2_tip_fee,
-            contract_address,
+            contract_address_as_bytes,
             l1_block_number.0 as i32,
             value,
             empty_address.as_bytes(),
@@ -161,7 +162,8 @@ impl TransactionsDal<'_, '_> {
     }
 
     pub async fn insert_system_transaction(&mut self, tx: &ProtocolUpgradeTx) -> DalResult<()> {
-        let contract_address = tx.execute.contract_address.as_bytes().to_vec();
+        let contract_address = tx.execute.contract_address;
+        let contract_address_as_bytes = contract_address.map(|addr| addr.as_bytes().to_vec());
         let tx_hash = tx.common_data.hash().0.to_vec();
         let json_data = serde_json::to_value(&tx.execute)
             .unwrap_or_else(|_| panic!("cannot serialize tx {:?} to json", tx.common_data.hash()));
@@ -238,7 +240,7 @@ impl TransactionsDal<'_, '_> {
             gas_per_pubdata_limit,
             json_data,
             upgrade_id,
-            contract_address,
+            contract_address_as_bytes,
             l1_block_number,
             value,
             &Address::default().0.to_vec(),
@@ -284,7 +286,8 @@ impl TransactionsDal<'_, '_> {
         }
 
         let initiator_address = tx.initiator_account();
-        let contract_address = tx.execute.contract_address.as_bytes();
+        let contract_address = tx.execute.contract_address;
+        let contract_address_as_bytes = contract_address.map(|addr| addr.as_bytes().to_vec());
         let json_data = serde_json::to_value(&tx.execute)
             .unwrap_or_else(|_| panic!("cannot serialize tx {:?} to json", tx.hash()));
         let gas_limit = u256_to_big_decimal(tx.common_data.fee.gas_limit);
@@ -413,7 +416,7 @@ impl TransactionsDal<'_, '_> {
             input_data,
             &json_data,
             tx_format,
-            contract_address,
+            contract_address_as_bytes,
             value,
             &paymaster,
             &paymaster_input,
@@ -697,8 +700,10 @@ impl TransactionsDal<'_, '_> {
                     .arg_error(&format!("transactions[{index_in_block}].refunded_gas"), err)
             })?;
 
+            let contract_address = transaction.execute.contract_address;
+            let contract_address_as_bytes = contract_address.map(|addr| addr.as_bytes().to_vec());
             l2_values.push(u256_to_big_decimal(transaction.execute.value));
-            l2_contract_addresses.push(transaction.execute.contract_address.as_bytes());
+            l2_contract_addresses.push(contract_address_as_bytes);
             l2_paymaster_input.push(&common_data.paymaster_params.paymaster_input[..]);
             l2_paymaster.push(common_data.paymaster_params.paymaster.as_bytes());
             l2_hashes.push(tx_res.hash.as_bytes());
@@ -818,7 +823,7 @@ impl TransactionsDal<'_, '_> {
             &l2_inputs as &[&[u8]],
             &l2_datas,
             &l2_tx_formats,
-            &l2_contract_addresses as &[&[u8]],
+            &l2_contract_addresses as &[Option<Vec<u8>>],
             &l2_values,
             &l2_paymaster as &[&[u8]],
             &l2_paymaster_input as &[&[u8]],
@@ -901,8 +906,10 @@ impl TransactionsDal<'_, '_> {
                     .arg_error(&format!("transactions[{index_in_block}].refunded_gas"), err)
             })?;
 
+            let contract_address = transaction.execute.contract_address;
+            let contract_address_as_bytes = contract_address.map(|addr| addr.as_bytes().to_vec());
             l2_values.push(u256_to_big_decimal(transaction.execute.value));
-            l2_contract_addresses.push(transaction.execute.contract_address.as_bytes());
+            l2_contract_addresses.push(contract_address_as_bytes);
             l2_paymaster_input.push(&common_data.paymaster_params.paymaster_input[..]);
             l2_paymaster.push(common_data.paymaster_params.paymaster.as_bytes());
             l2_hashes.push(tx_res.hash.as_bytes());
@@ -1013,7 +1020,7 @@ impl TransactionsDal<'_, '_> {
             &l2_datas,
             &l2_refunded_gas,
             &l2_values,
-            &l2_contract_addresses as &[&[u8]],
+            &l2_contract_addresses as &[Option<Vec<u8>>],
             &l2_paymaster as &[&[u8]],
             &l2_paymaster_input as &[&[u8]],
             l2_block_number.0 as i32,
@@ -1083,6 +1090,8 @@ impl TransactionsDal<'_, '_> {
                     .arg_error(&format!("transactions[{index_in_block}].refunded_gas"), err)
             })?;
 
+            let contract_address = transaction.execute.contract_address;
+            let contract_address_as_bytes = contract_address.map(|addr| addr.as_bytes().to_vec());
             let tx = &tx_res.transaction;
             l1_hashes.push(tx_res.hash.as_bytes());
             l1_initiator_address.push(common_data.sender.as_bytes());
@@ -1096,7 +1105,7 @@ impl TransactionsDal<'_, '_> {
             l1_priority_op_id.push(common_data.serial_id.0 as i64);
             l1_full_fee.push(u256_to_big_decimal(common_data.full_fee));
             l1_layer_2_tip_fee.push(u256_to_big_decimal(common_data.layer_2_tip_fee));
-            l1_contract_address.push(tx.execute.contract_address.as_bytes());
+            l1_contract_address.push(contract_address_as_bytes);
             l1_l1_block_number.push(common_data.eth_block as i32);
             l1_value.push(u256_to_big_decimal(tx.execute.value));
             l1_tx_format.push(common_data.tx_format() as i32);
@@ -1203,7 +1212,7 @@ impl TransactionsDal<'_, '_> {
             &l1_priority_op_id,
             &l1_full_fee,
             &l1_layer_2_tip_fee,
-            &l1_contract_address as &[&[u8]],
+            &l1_contract_address as &[Option<Vec<u8>>],
             &l1_l1_block_number,
             &l1_value,
             &l1_tx_format,
@@ -1373,6 +1382,8 @@ impl TransactionsDal<'_, '_> {
                     .arg_error(&format!("transactions[{index_in_block}].refunded_gas"), err)
             })?;
 
+            let contract_address = transaction.execute.contract_address;
+            let contract_address_as_bytes = contract_address.map(|addr| addr.as_bytes().to_vec());
             let tx = &tx_res.transaction;
             upgrade_hashes.push(tx_res.hash.as_bytes());
             upgrade_initiator_address.push(common_data.sender.as_bytes());
@@ -1385,7 +1396,7 @@ impl TransactionsDal<'_, '_> {
                     .unwrap_or_else(|_| panic!("cannot serialize tx {:?} to json", tx.hash())),
             );
             upgrade_upgrade_id.push(common_data.upgrade_id as i32);
-            upgrade_contract_address.push(tx.execute.contract_address.as_bytes());
+            upgrade_contract_address.push(contract_address_as_bytes);
             upgrade_l1_block_number.push(common_data.eth_block as i32);
             upgrade_value.push(u256_to_big_decimal(tx.execute.value));
             upgrade_tx_format.push(common_data.tx_format() as i32);
@@ -1484,7 +1495,7 @@ impl TransactionsDal<'_, '_> {
             &upgrade_gas_per_pubdata_limit,
             &upgrade_data,
             &upgrade_upgrade_id,
-            &upgrade_contract_address as &[&[u8]],
+            &upgrade_contract_address as &[Option<Vec<u8>>],
             &upgrade_l1_block_number,
             &upgrade_value,
             &upgrade_tx_format,

core/lib/mempool/src/tests.rs

@@ -371,7 +371,7 @@ fn gen_l2_tx(address: Address, nonce: Nonce) -> Transaction {
 
 fn gen_l2_tx_with_timestamp(address: Address, nonce: Nonce, received_at_ms: u64) -> Transaction {
     let mut txn = L2Tx::new(
-        Address::default(),
+        Some(Address::default()),
         Vec::new(),
         nonce,
         Fee::default(),
@@ -386,7 +386,7 @@ fn gen_l2_tx_with_timestamp(address: Address, nonce: Nonce, received_at_ms: u64)
 
 fn gen_l1_tx(priority_id: PriorityOpId) -> Transaction {
     let execute = Execute {
-        contract_address: Address::repeat_byte(0x11),
+        contract_address: Some(Address::repeat_byte(0x11)),
         calldata: vec![1, 2, 3],
         factory_deps: vec![],
         value: U256::zero(),

core/lib/multivm/src/versions/vm_1_3_2/test_utils.rs

@@ -153,7 +153,7 @@ pub fn get_create_execute(code: &[u8], calldata: &[u8]) -> Execute {
         .expect("failed to encode parameters");
 
     Execute {
-        contract_address: CONTRACT_DEPLOYER_ADDRESS,
+        contract_address: Some(CONTRACT_DEPLOYER_ADDRESS),
         calldata,
         factory_deps: vec![code.to_vec()],
         value: U256::zero(),

core/lib/multivm/src/versions/vm_1_3_2/transaction_data.rs

@@ -22,7 +22,7 @@ use crate::vm_1_3_2::vm_with_bootloader::{
 pub struct TransactionData {
     pub tx_type: u8,
     pub from: Address,
-    pub to: Address,
+    pub to: Option<Address>,
     pub gas_limit: U256,
     pub pubdata_price_limit: U256,
     pub max_fee_per_gas: U256,
@@ -170,7 +170,7 @@ impl TransactionData {
         encode(&[Token::Tuple(vec![
             Token::Uint(U256::from_big_endian(&self.tx_type.to_be_bytes())),
             Token::Address(self.from),
-            Token::Address(self.to),
+            Token::Address(self.to.unwrap_or_default()),
             Token::Uint(self.gas_limit),
             Token::Uint(self.pubdata_price_limit),
             Token::Uint(self.max_fee_per_gas),
@@ -593,7 +593,7 @@ mod tests {
         let transaction = TransactionData {
             tx_type: 113,
             from: Address::random(),
-            to: Address::random(),
+            to: Some(Address::random()),
             gas_limit: U256::from(1u32),
             pubdata_price_limit: U256::from(1u32),
             max_fee_per_gas: U256::from(1u32),

core/lib/multivm/src/versions/vm_1_4_1/tests/gas_limit.rs

@@ -21,10 +21,8 @@ fn test_tx_gas_limit_offset() {
     let gas_limit = 9999.into();
     let tx = vm.rich_accounts[0].get_l2_tx_for_execute(
         Execute {
-            contract_address: Default::default(),
-            calldata: vec![],
-            value: Default::default(),
-            factory_deps: None,
+            contract_address: Some(Default::default()),
+            ..Default::default()
         },
         Some(Fee {
             gas_limit,

core/lib/multivm/src/versions/vm_1_4_1/types/internals/transaction_data.rs

@@ -22,7 +22,7 @@ use crate::vm_1_4_1::{
 pub(crate) struct TransactionData {
     pub(crate) tx_type: u8,
     pub(crate) from: Address,
-    pub(crate) to: Address,
+    pub(crate) to: Option<Address>,
     pub(crate) gas_limit: U256,
     pub(crate) pubdata_price_limit: U256,
     pub(crate) max_fee_per_gas: U256,
@@ -169,7 +169,7 @@ impl TransactionData {
         encode(&[Token::Tuple(vec![
             Token::Uint(U256::from_big_endian(&self.tx_type.to_be_bytes())),
             Token::Address(self.from),
-            Token::Address(self.to),
+            Token::Address(self.to.unwrap_or_default()),
             Token::Uint(self.gas_limit),
             Token::Uint(self.pubdata_price_limit),
             Token::Uint(self.max_fee_per_gas),
@@ -311,7 +311,7 @@ mod tests {
         let transaction = TransactionData {
             tx_type: 113,
             from: Address::random(),
-            to: Address::random(),
+            to: Some(Address::random()),
             gas_limit: U256::from(1u32),
             pubdata_price_limit: U256::from(1u32),
             max_fee_per_gas: U256::from(1u32),

core/lib/multivm/src/versions/vm_1_4_2/tests/gas_limit.rs

@@ -20,10 +20,8 @@ fn test_tx_gas_limit_offset() {
     let gas_limit = 9999.into();
     let tx = vm.rich_accounts[0].get_l2_tx_for_execute(
         Execute {
-            contract_address: Default::default(),
-            calldata: vec![],
-            value: Default::default(),
-            factory_deps: None,
+            contract_address: Some(Default::default()),
+            ..Default::default()
         },
         Some(Fee {
             gas_limit,

core/lib/multivm/src/versions/vm_1_4_2/types/internals/transaction_data.rs

@@ -22,7 +22,7 @@ use crate::vm_1_4_2::{
 pub(crate) struct TransactionData {
     pub(crate) tx_type: u8,
     pub(crate) from: Address,
-    pub(crate) to: Address,
+    pub(crate) to: Option<Address>,
     pub(crate) gas_limit: U256,
     pub(crate) pubdata_price_limit: U256,
     pub(crate) max_fee_per_gas: U256,
@@ -169,7 +169,7 @@ impl TransactionData {
         encode(&[Token::Tuple(vec![
             Token::Uint(U256::from_big_endian(&self.tx_type.to_be_bytes())),
             Token::Address(self.from),
-            Token::Address(self.to),
+            Token::Address(self.to.unwrap_or_default()),
             Token::Uint(self.gas_limit),
             Token::Uint(self.pubdata_price_limit),
             Token::Uint(self.max_fee_per_gas),
@@ -311,7 +311,7 @@ mod tests {
         let transaction = TransactionData {
             tx_type: 113,
             from: Address::random(),
-            to: Address::random(),
+            to: Some(Address::random()),
             gas_limit: U256::from(1u32),
             pubdata_price_limit: U256::from(1u32),
             max_fee_per_gas: U256::from(1u32),

core/lib/multivm/src/versions/vm_boojum_integration/tests/gas_limit.rs

@@ -21,10 +21,8 @@ fn test_tx_gas_limit_offset() {
     let gas_limit = 9999.into();
     let tx = vm.rich_accounts[0].get_l2_tx_for_execute(
         Execute {
-            contract_address: Default::default(),
-            calldata: vec![],
-            value: Default::default(),
-            factory_deps: None,
+            contract_address: Some(Default::default()),
+            ..Default::default()
         },
         Some(Fee {
             gas_limit,